Nitrate
West Salem Waterworks
Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 0.00300 ppm | 3 | 2 | ND - 0.00700 ppm |
| 2019 | 0.00267 ppm | 3 | 1 | ND - 0.00800 ppm |
| 2020 | 0.00467 ppm | 3 | 3 | 0.00300 ppm - 0.00700 ppm |
| 2021 | 0.00433 ppm | 3 | 1 | ND - 0.0130 ppm |
| 2022 | 0.0140 ppm | 3 | 2 | ND - 0.0310 ppm |
| 2023 | 0.00633 ppm | 3 | 3 | 0.00400 ppm - 0.00900 ppm |
ppm = parts per million
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.14 ppm
The EWG health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.
EPA Maximum Contaminant
Level (MCL): 10 ppm
The legal limit for nitrate, established in 1962, was developed to protect infants from acute methemoglobinemia, a life-threatening disorder of oxygen transport in the body. This limit does not fully protect against the risk of cancer and harm to the developing fetus.
ppm = parts per million
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-08-09 | 18H0387-03 | 0.00200 ppm |
| 2018-08-09 | 18H0387-01 | 0.00700 ppm |
| 2018-08-09 | 18H0387-02 | ND |
| 2019-07-24 | 19G0846-03 | ND |
| 2019-07-24 | 19G0846-02 | ND |
| 2019-07-24 | 19G0846-01 | 0.00800 ppm |
| 2020-06-03 | 20F0131-03 | 0.00300 ppm |
| 2020-06-03 | 20F0131-01 | 0.00400 ppm |
| 2020-06-03 | 20F0131-02 | 0.00700 ppm |
| 2021-06-09 | 21F0319-03 | ND |
| 2021-06-09 | 21F0319-01 | 0.0130 ppm |
| 2021-06-09 | 21F0319-02 | ND |
| 2022-02-24 | 22B0759-01 | ND |
| 2022-03-24 | 22C0767-01 | 0.0310 ppm |
| 2022-04-21 | 22D0604-02 | 0.0110 ppm |
| 2023-02-09 | 23B0296-01 | 0.00400 ppm |
| 2023-02-16 | 23B0478-01 | 0.00900 ppm |
| 2023-02-23 | 23B0667-01 | 0.00600 ppm |